Continuously-operating multiple lathe



Nov. 18, 1930. F. M. DAVIS ET AL' 1,782,138

CONTINUOUSLY OPERATING MULTIPLE LATHE Filed April 2 1926 5 Sheets-Sheet 1 WITNESSES. 5/ Q i; INVENTORS 6% ATTORNEY.

7 NOV. 18, 1930. F, DAVIS E AL 1,782,138

CONTINUOUSLY OPERATING MULTIPLE LATHE Filed pril 22, 1926 5 Sheets-Sheet 2 I I'll INVENTORS FZMQWXQAQ ATTORNEY.

Nov. 18, 1930. F. M. DAVIS ET AL CONTINUOUSLY OPERATING MULTIPLE LATHE 3 Sheets-:Sheec 3 Filed April 22, 1926' INVENTORS Q 4 ATTORNEY.

m QZA QM Q WITNESSES.

Patented Nov. 18, 1 930 4 I UNITED STATES PATENT OFFICE FRANK M. DAVIS, OF MILWAUKEE, WISCONSIN, AND ALBERT C. HOEH, OF PONTIAC,

MICHIGAN, ASSIGNORS TO DAVIS 85 THOMPSON COMPANY, OF MILWAUKEE, WIS- CONSIN, A CORPORATION OF WISCONSIN CON TIN 'UOU'SLY -O'PERATIN G MULTIPLE LATHE ,Application filed April 22,

The invention relates to machine tools equipped with a plurality of spindles, and more particularly to the type in which a group of lathes is mounted on a rotary car rier for operating on a plurality of work pieces.

Rotary multiple spindle machines, as heretofore developed for quantity production Work, have incorporated numerous internal working parts. When repairs or replace ments are required on a machine of this type, it is usually necessary to dismantle the entire machine, which requires considerable labor and may place the machine out of operation forseveral days, thus greatly interfering with production schedules. Also, these machines have been of complicated and expensive construction and have been of such character as to restrict their application to limited classes of work.

An object of the present invention is to provide a rotary multiple spindle machine in which the parts are so arranged as to simplify the construction, and wherein the working parts are disposed in accessible positions removed from the rotatable column which carries the spindles. I

, Another object of the invention is to provide a machine of this character in which the spindles are independently driven but which co-operate with a common feeding means.

A further object of the invention is to provide a machine in which a rotary vertical column forms a carrier on which a plurality of independently-driven machine tools, such as laths, drill presses or the like, may be mounted.

A further object of the invention is to provide a machine of this character with a stationary upper end having annular bus-bars thereon forming tracks for supplying the spindle motors with current. A further object is to provide clutches for the motor-driven spindles and cam means operative to release the clutches in the load ing position of the machine.

The invention further consists in the several features hereinafter set forth and more particularly defined by the annexed claims.

In the accompanying drawings, Fig. 1 is 1926. Serial No. 103,839.

an elevation of a machine embodying the invention, parts being broken away and parts being shown in section;

- Fig. 2 is an elevation of a rotary carrier with the spindles removed;

Fig. Bis a transverse sectional view taken on the line 33 of Fig. 1;

. Fig. 4 is a schematic elevation of the clutchoperating means; 1 Fig. 5 is a detail sectional the line 5-5 of Fig. 2; and

Fig. 6 is a detail sectional view taken on the line 66 of Fig. 2.

In these drawings, 10 indicates a hollow annular base within which is secured a hollow upwardly projecting vertical column 11.

A cover or top plate 12 is secured tothe upper end of the column 11 and is provided with a cylindrical flanged rim portion 13 somewhat larger than and concentric with the column 11. A polygonal drum 14 forming a rotary spindle carrier is journalled at opposite ends on the column 11 and is confined thereon between the base 10 and the top plate 12. An annular lubricant well 15 is formed in the upper art of the base 10 and receives a ball thrust bearing 16 for supporting the carrier 14. The lower end of the carrier 14 has secured to it for rotation therewith spindle view taken on 60 an annularcylindrical drum 17 for guiding 8o feeding means hereinafter described, and an annular downwardly flared apron 18 is socured to the upper part of the drum 17 for excluding chips and other foreign matter from the lower working parts.

The top plate 12 forms part of a gear housing on which is mounted an electric motor 19 for driving the rotatable carrier 14. For this purpose the carrier is provided with a bevel ring gear 20 at its upper end which is meshed at diametrically opposite points with bevel driving pinions 21 secured to shafts 22 journalled in bearings 23 preferably formed integrally with the top plate 12 and inclined with their upper ends directed towards the axis of the carrier. Worm wheels 24: are secured to the upper ends of the shafts 22 and mesh with worms 25 at their adjacent portions driven by the motor 19 through suitable intermediate gearing, so that the carrier may rotate at a comparatively low speed. By driving the ring gear .at diametrically opposite points, it is possible to balance the driving torque so as to relieve theupper bearing of any substantial radial load and to insure smooth rotation.

In the present instance, the carrier drum 14 is hexagonal and includes fiat faces 26 each provided with a number of bolt holes 27 and a vertically extending key groove 28. The fiat faces of the carrier drum are adapted to receive spindle units, herein designated generally as 29, which may assume any suitable character according to the kind of operations desired. In the present embodiment of the invention, these spindle 'units are in the form of lathes each including a bed 30 secured to a face of the drum by bolts 31 and accurately positioned thereon by means of a key projection 32 fitting in the groove 28. The head stock 33 of each lathe is disposed atthe upper end of the carrier and includes a depending spindle 34 driven by an electric motor 35 through suitable intermediate gearing and a clutch 36 actuated by mechanism hereinafter described, A tail stock 37 is mounted at the lower end of each lathe and carries a lever mechanism 38 for moving and locking the usual dead center 39, when the character of the work piece 40 requires it. The spindle 34 may be equipped with the usual chuck 41 or a face plate. A carriage 42 slidably mounted for vertical movement on ways on the lathe bed 30 may be provided with the usual tool holder 43 receiving a cutting tool 44. A cam ring 45 is secured to the base 10 by bolts 46' and is formed in separable flanged sections so that it may be readily changed to provide a diiferent cam "profile when desired without dismantling the machine. Each carriage 42 is reciprocated by vmeans of a roller 47 riding on the cam ring and mounted on a T-block 48 connected to the carriage by a vertically extending threaded rod 49, the carria e being positioned upon the rod by'means o clamping nuts 50. Each T-block 48 is guided in a.vertically-extending T-slot 51 formed in the cylindrical drum 17 which rotates with the carrier drum 14, and each rod 49 also passes through a bracket 52 which furnishes additional support for the apron 18.

The cam ring 45 is constructed to provide a cycle of operation durin each revolution of the carrier drum 14 an includes a dwell 53 at the lowermost part of the cam edge adjacent to the loading station of the machine. When the rollers 47 assthis dwell the tool carriages 42 are at t eir lowermost position and during this period opportunity 1s given the operator for. removing the. finished work ieces and replacing them by other unfini ed pieces. The slope of'the cam path may be variable as shown according to the permissible feed, and the drop from the uppermost part of the cam ring to the dwell is slightly inclined to avoid sudden dropping of the rollers.

In order to permit loading and unloading of the machine, it is necessary to stop the rotation of the spindles for the period during which each spindle passes the loading station, and this is accomplished by controlling the'spindle clutches 36, as shown schematically in Fig. 4. A circular rib 54 is formed at the rim 13 of the top plate 12 and has its ends spaced and provided with cam shoes 55. A cam projection 56 is secured to the rim 13 above and between the ends of the rib 54 and has inclined cam surfaces 57 at its ends spaced from and substantially parallel to the upper cam surfaces of the cam shoes 55. Each clutch 36 includes a movable jaw member 58 engaged by a shifting collar 59 trunnioned in a lever 60 pivoted on a stationary pin 61. The free end of the lever 60 is provided with a fork 62 engaging a pin 63 secured to a verticallydisposed rack 64 slidably mounted in a stationary housing 65 Where the rack meshes with a segmental gear 66 journalled on a pin 67. A companion. segmental gear 68 is also j ournalled on the pin 67 and is meshed with a rack 69. at the upper end of which a roller 70 is pivotally mounted to ride on the upper edge of the cam rib 54 and on the lower edge of the cam projection 56. The lower edges of the segmental gears 66 and 68 are ur ed into abutment by a spring 71 disposed etween the upper parts of these gears so that a positive driving connection is formed in onedirection of rotation and a yielding connection in the other direction. The cam projection 56 is so placed on the periphery of the rim 13 that the roller 70 will be depressed thereby when the'lathe reaches the loading station, the depression of the roller 70 serving to effect the release of the movable jaw member 58 of the clutch through the intermediate linkage including the racks and segmental gears. When the lathe is about to leave the loading station the roller 70 is forced upwardly along the cam shoe 55 onto the upper edge of'the cam rib 34, thus efiecting. engagement of the clutch 36 through the interposed linkage. In this case, however, the spring 71. interposed between thegear segments 66 and 68 provides a yield- For drilling operations the spindle chucks may be adapted to receive drills and the work maybe secured directly to the'movable carria es 42 eachof which may be' suitably mo ified if'desired to ,include a horizontal table. In this case, it is not necessary to stop the rotation'of thespindleat the loading'station. The spindle motors 35 are each-supplied with current-througha set-ofbruShes 72 tier mounted on an upwardly projecting standard 73 and bearing against stationary circular bus-bars 74 which are mounted on a cylindrical sheet of insulating material 75 secured at its lower edge tothe rim 13 of the top plate.12 and at its upper edge to an annular re-ehforcing ring 76. The circular busbars 74 are preferably greater in number than the supply lines so as to avoid concentration of the entire spindle motor load on the same bus-bar. Each spindle motor carries a switch 80 and all the switches are suitably interconnected so that overloading or disablingv of any spindle motor will stop the remaining spindle motors as well as the carrier drum motor, and vice versa.

A clutch 77 interposed in the driving connection between the. carrier motor and the carrier drum is mounted adjacent the carrier motor 19 for controlling the rotation of the carrier drum and is provided with an arm 78 having a depending actuating rod 79 disposed convenient to the operator. By this means the rotation of the carrier may be stopped without stopping the spindle units, so that examination and adjustment of the cut may be madewithout shutting down the spindle motor or starting them under load.

In operation, the attendant stands at the loading station and, after starting the spindle motors but permitting the carrier to remain stationary, places-a work piece in the chuck of the adjacent spindle which is then stationary by reason of the release of the clutch 36 when the roller 70 is depressed by the cam projection 56 on the rim of the top plate 12. The dead center 39 is then lifted and retained by the lever mechanism 38 into engagement with the lower end of the work piece, after which the carrier is started in rotation. After passing the loading station, the spindle is started in rotation by the spindle motor through the clutch 36, which is engaged as the roller 70 is lifted by the cam shoe to ride on the upper surface of the cam rib 54. The tool carriage 42, which is then in its lowermost position, is moved up wardly along its ways by the elevation of the cam roller 47 along the cam ring 45. As successive lathes pass the loading station, they are supplied with Work pieces in the same manner, and when the first loaded lathe again reaches the loading station, the tool carriage 42 has traversed its upward movement during which the cutting operation on the work I piece is completed. The roller 47 then descends into the dwell 53 of the cam ring 45 and at the same time the clutch-actuating roller is depressed by the cam projection 56 to release the clutch 36 and stop the rotation of the spindle to permit removal of the finished work piece. A new work piece is then supplied tothe lathe immediately following the removal of the finished work piece and the cycle of operation is then repeated.

It will be seen that the construction of the carrier drum is such-that it may receive any appropriate type of machine tool unit, lathe units being shown in the present embodiment of the invention. In the case of drill press units the movable carriages reciprocated by means of the cam ring can be used as tables for receiving the work pieces. As the spindle units are independently motor driven the necessity for any driving connection from the carrier drum motor is avoided which greatly simplifies the construction and provides accessibility of parts so that replacement of parts when necessary can be effected in a very short time. The character of the machine also facilitates manufacturing operations as the same carrier may have alternatively secured to it different sets of spindle units. WVhat We claim as new and desire to secure by Letters Patent is:

1. In combination, a. base and a central column secured thereto, a rotatable carrier surrounding said column and having a guide member at its lower end rotatable therewith, vertical guide-ways formed in said guide member, a cam ring secured to said base and surrounding said guide member, a plurality of spindle units mounted about said carrier for rotation therewith, a vertically reciprocable carriage for each spindle unit, aconnecting rod depending from each carriage and having its lower end guided for vertical movement in said guide-ways, and a roller mounted at the lower end of each connecting rod and riding on the cam ring surrounding the guide-Ways, said cam ring being capable of removal and replacement without dismantling other mechanism.

2. In ,combination, a rotatable carrier mounted to rotate on a vertical axis and havihg a polygonal exterior forming fiat faces,

and a plurality of independently-motor- I driven self-contained spindle units removably secured to the faces of said carrier. L

3. In combination, a rotatable carrier, 9.

plurality of motor-driven spindle units se- I cured to said carrier, a plurality of circular bus-bars disposed at the upper end of said carrier and concentric therewith, and brush gear movable with the spindle units as they rotate with the carrier for conveying current from said bus-bars to the motors of the spindle units.

4. In combination, a rotatable carrier having fiat exterior faces parallel to its axis, and self-contained-motor-driven machine tool units each having a bed removably secured to a faceof the carrier, each bed and carrier face having a tongue and groove connection for aligning the machine tool unit on the carrier.

5. In combination, a rotatable carrier having a plurality of spindle units thereon, individual clutches for said spindle units, and

meanstfor controlling the periodic actuation of said clutches during the rotation of said 4 carrier including linkage, said'linkage comprising a pair of racks, a pair of coaxial se mental gears each meshing with one of said racks and resilient drivlng means interposed between said'gears for transmitting clutch-actuating motion through said linkage. p

6. In combination, a rotatable carrier, means for rotating said carrier, a plurality of independently-driven work-carrying machine tool units secured to said carrier for rotation therewith, each machine tool unit pendently removable as a being independently removable as a whole from said carrier,-a movable carriage slidably mounted on and forming a part of each machine tool unit, and means for reciprocating said carriage during the rotation of said carrier.

7. In combination, a rotatable carrier, means for rotating said carrier, a plurality of machine tool units mounted on said carrier for rotation therewith and each unit includin a driving motor forming a part thereo each machine tool unit being indewhole from said carrier, a clutch forming part of each machine tool unit for controlling thedriving connection of the motor, and automatic means for successively operating the clutches f motors o of the machine tool units during the rotation of the carrier.

8. In combination, a rotatable carrier, a

ring comprising a plurality of complementary segmental sections disposed in abutment and separably secured in place to render them capable of removal'and replacement without disturbing other mechanism.

I 10, The combination of a base and a columnar standard projecting upwardly therefrom, a'carrier surrounding said standard and rotatable for driving the carrier, and self-contained motor-driven machine tool units mounted on; the exterior of said carrier, whereby interior portions of said standard and said base are kept free from operating arts.

11." he combination of a rotatable carrier, means including an electric motor for gear movable with the machine tool driving said carrier, a plurality of self-contained' machine tool units mounted on said carrier and each including an electric driving motor and a clutch, means for automatically operating the clutches of said machine tool units during the rotation of said carrier, anda clutch between the carrier and its driving motor for controlling the operation of said carrier independently of said machine tool units.

In testimony whereof, we atfix our signatures.

FRANK M. DAVIS. ALBERT C. I-IOEH. 

